JP7218581B2 - Method for producing solid catalyst component for α-olefin polymerization, catalyst for α-olefin polymerization, and method for producing α-olefin polymer using the same - Google Patents

Description

The present invention relates to a method for producing a solid catalyst component for α-olefin polymerization, a catalyst for α-olefin polymerization, and a method for producing an α-olefin polymer using the same.

Polyolefins such as polyethylene and polypropylene are the most important plastic materials as industrial materials. Films and sheets are used as packaging materials and electrical materials. Molded products are used as industrial materials such as automobile parts and home appliances. It is widely used in various applications such as building materials.
Due to such a wide variety of uses, polyolefins continue to be required to be improved and improved in various properties from the standpoint of their use. technology has been developed by

Ziegler-type catalysts using transition metal compounds and organometallic compounds greatly enhanced the polymerization activity of olefins and made industrial production possible. Various performance improvements have been made, including improvements in the stereoregularity of olefins.
Specifically, a catalyst using a magnesium compound as a catalyst carrier and a solid catalyst component containing titanium and halogen as essential components has been developed, and a catalyst with enhanced catalytic activity and stereoregularity using an electron donor. (See, for example, Patent Documents 1 to 3), and thereafter, a proposal was made to further add a specific organosilicon compound to the catalyst component to further improve catalytic activity and stereoregularity (Patent Documents 1 to 3). 4). In addition to the specific organosilicon compound, by using a silicon compound with a special structure having an alkenyl group such as a vinyl group or an allyl group, catalytic activity and stereoregularity are further improved, and it can be used as a molecular weight modifier. Proposals have also been made to improve the performance, such as by improving the response of the hydrogen used (see Patent Documents 5 to 8, for example). Furthermore, it has been proposed to reduce amorphous components by using a specific amide compound or sulfite ester in combination with an organosilicon compound as an external donor (see Patent Documents 9 and 10). In addition, many improvement techniques have been disclosed, such as improving stereoregularity by treating a solid catalyst component with two types of specific organoaluminum compounds twice or more (see, for example, Patent Document 11).

JP-A-58-138706 JP-A-57-59909 JP-A-58-147409 JP-A-62-187707 JP-A-03-234707 JP-A-07-2923 JP 2006-169283 A JP 2008-163151 A Japanese Patent Application Laid-Open No. 2004-124090 JP 2006-225449 A Japanese Unexamined Patent Application Publication No. 2001-40028

However, as far as the present researchers know, in any of these catalyst systems, improvements in various properties such as the stereoregularity of the α-olefin polymer produced and the reduction of amorphous components are still insufficient. However, in each field of application, improvements in various properties are required. Further improvements in the reduction of dissolved amorphous components are desired, and in the field of packaging materials, further improvements in stickiness and the like are also strongly desired.

The object of the present application is to further increase the rigidity of the amorphous component in order to meet the demand for further performance improvement from a wide range of application fields in the state of the above-described prior art in the field of polyolefin materials and catalysts for olefin polymerization. It is an object of the present invention to provide a catalyst capable of producing an α-olefin polymer with reduced polystyrene and improved stereoregularity, and a method for producing an α-olefin polymer using the catalyst.

As a result of intensive research to achieve the above object, the present researchers have found that an olefin polymer with low soluble content and high stereoregularity can be obtained in high yield, the amount of electron donor is extremely small, and found an α-olefin polymerization catalyst containing a solid catalyst component for α-olefin polymerization containing an alkoxysilane compound.

The method for producing a solid catalyst component for α-olefin polymerization of the present invention is a method for producing a solid catalyst component (A) for α-olefin polymerization containing magnesium, titanium, halogen, an electron donor and an alkoxysilane compound,
The following component (A1) is contacted with the component (A2), the component (A3) and the component (A4) at a temperature of 50 to 110 ° C.,
The content of the electron donor in the obtained solid catalyst component (A) for α-olefin polymerization is 40 μmol/g or less.
Component (A1): Solid component containing titanium, magnesium, halogen and an electron donor as essential components Component (A2): Silane compound having an alkenyl group Component (A3): Alkoxysilane compound [wherein the silane compound having an alkenyl group different from ]
Component (A4): Organoaluminum compound

In the method for producing a solid catalyst component for α-olefin polymerization of the present invention, the component (A1) consists of ethylene, propylene, 1-butene and 3-methyl-1-butene in the presence of an organoaluminum compound. It may be prepolymerized with at least one olefin selected from the group.

In the method for producing a solid catalyst component for α-olefin polymerization of the present invention, the component (A2) may be a vinylsilane compound.

In the method for producing a solid catalyst component for α-olefin polymerization of the present invention, the component (A3) may be a silicon compound represented by the following general formula (1).
R ¹ R ² _m Si(OR ³ ) _n (1)
(wherein R ¹ represents a hydrocarbon group or a heteroatom-containing hydrocarbon group; R ² represents any free radical selected from hydrogen, halogen, hydrocarbon groups and heteroatom-containing hydrocarbon groups; R ³ represents It is a hydrocarbon group and represents 0≦m≦2, 1≦n≦3, and m+n=3.)

The α-olefin polymerization catalyst of the present invention is characterized by comprising the solid catalyst component (A) for α-olefin polymerization obtained by the production method described above and the following component (B).
Component (B): Organoaluminum compound

The method for producing an α-olefin polymer of the present invention is characterized by homopolymerizing or copolymerizing an α-olefin using the α-olefin polymerization catalyst.

INDUSTRIAL APPLICABILITY According to the present invention, an olefin polymer having a low soluble content and high stereoregularity can be obtained in a high yield. A catalyst for alpha-olefin polymerization can be provided comprising a catalyst component.

1. Method for producing a solid catalyst component for α-olefin polymerization (A) A method for producing a solid catalyst component for α-olefin polymerization of the present invention is for α-olefin polymerization containing magnesium, titanium, halogen, an electron donor and an alkoxysilane compound. A method for producing a solid catalyst component (A), comprising:
The following component (A1) is contacted with the component (A2), the component (A3) and the component (A4) at a temperature of 50 to 110 ° C.,
The content of the electron donor in the obtained solid catalyst component (A) for α-olefin polymerization is 40 μmol/g or less.
Component (A1): Solid component containing titanium, magnesium, halogen and an electron donor as essential components Component (A2): Alkenyl group-containing silane compound Component (A3): Alkoxysilane compound [wherein the alkenyl group-containing silane compound different from ]
Component (A4): Organoaluminum compound

Each item of the solid catalyst component for α-olefin polymerization obtained by the production method of the present invention will be described in detail below. In this specification, the term "to" indicating a numerical range is used to include the numerical values before and after it as lower and upper limits.

1-1. Solid component (A1)
The solid component (A1) of the present invention contains magnesium (A1a-1), titanium (A1a-2), halogen (A1a-3) and electron donor (A1a-4) as essential components.

1-1-1. Magnesium (A1a-1)
Any magnesium compound can be used as the magnesium source used in the solid component (A1) according to the present invention. A representative example thereof is the compound disclosed in JP-A-3-234707.
In general, magnesium halide compounds typified by magnesium chloride, alkoxymagnesium compounds typified by diethoxymagnesium, metallic magnesium, oxymagnesium compounds typified by magnesium oxide, and magnesium hydroxide are typified. Hydroxymagnesium compounds, Grignard compounds typified by butylmagnesium chloride, organomagnesium compounds typified by butyloctylmagnesium, magnesium salt compounds of inorganic and organic acids typified by magnesium carbonate and magnesium stearate, and A mixture thereof, a compound whose average compositional formula is a mixed formula thereof (for example, a compound such as Mg(OEt) _m Cl _2-m ; 0<m<2, etc.) can be used.
Among these, magnesium chloride, diethoxymagnesium, metallic magnesium, and butylmagnesium chloride are particularly preferred.

In particular, when producing large particles, it is preferable to use dialkoxymagnesium because the particle size of the catalyst can be easily controlled. As dialkoxymagnesium, not only those produced in advance can be used, but those obtained by reacting alcohol with metallic magnesium in the presence of halogen or halogen-containing metal compounds in the catalyst production process can also be used. .

Furthermore, in the present invention, the dialkoxymagnesium suitable as the component (A1a-1) is granular or powdery, and its shape may be amorphous or spherical.
For example, when spherical dialkoxymagnesium is used, a polymer powder having a better particle shape and a narrower particle size distribution can be obtained, and the resulting polymer powder can be handled more easily during polymerization. Problems such as clogging due to fine powder contained in are resolved.

The above-mentioned spherical dialkoxymagnesium does not necessarily have to be truly spherical, and elliptical or potato-shaped ones can also be used. Specifically, the shape of the particles is such that the ratio (l/w) of the major axis diameter l to the minor axis diameter w is 3 or less, preferably 1 to 2, more preferably 1 to 1.5. be.
In addition, dialkoxymagnesium having an average particle size of 1 to 200 μm can be used. It is preferably 5 to 150 μm. In the case of spherical dialkoxymagnesium, its average particle size is 1 to 100 μm, preferably 5 to 50 μm, more preferably 10 to 40 μm.
As for the particle size, it is desirable to use those having a narrow particle size distribution with little fine powder and coarse powder. Specifically, particles of 5 μm or less are 20% or less, preferably 10% or less. On the other hand, particles of 100 μm or more are 10% or less, preferably 5% or less.
Furthermore, when the particle size distribution is represented by ln (D90/D10) (here, D90 is the particle size at 90% of the cumulative particle size, and D10 is the particle size at 10% of the cumulative particle size), it is 3 or less, It is preferably 2 or less.

Methods for producing spherical dialkoxymagnesium as described above are disclosed, for example, in JP-A-58-41832, JP-A-62-51633, JP-A-3-74341, JP-A-4-368391 and JP-A-4-368391. This is exemplified in Japanese Laid-Open Patent Publication No. 8-73388.

1-1-2. Titanium (A1a-2)
Any titanium compound can be used as the titanium source for the solid component (A1) according to the present invention. A typical example is the compound disclosed in JP-A-3-234707.
Regarding the valence of titanium, titanium compounds having any valence of tetravalent, trivalent, divalent and zero can be used, preferably tetravalent and trivalent titanium compounds, more preferably tetravalent It is desirable to use a titanium compound of

Specific examples of the tetravalent titanium compound include halogenated titanium compounds typified by titanium tetrachloride, alkoxytitanium compounds typified by tetrabutoxytitanium, tetrabutoxytitanium dimer (BuO) ₃ Ti—O—Ti ( Condensed compounds of alkoxy titanium having a Ti--O--Ti bond typified by OBu) ₃ , organometallic titanium compounds typified by dicyclopentadienyl titanium dichloride, and the like can be mentioned. Among these, titanium tetrachloride and tetrabutoxytitanium are particularly preferred.
Further, specific examples of the trivalent titanium compound include halogenated titanium compounds represented by titanium trichloride. Titanium trichloride can be a compound produced by any known method such as a hydrogen reduction type, a metal aluminum reduction type, a metal titanium reduction type, an organic aluminum reduction type, and the like.
The above titanium compounds can be used not only singly, but also in combination with a plurality of compounds. In addition, mixtures of the above titanium compounds, compounds whose average compositional formula is a mixed formula thereof (for example, compounds such as Ti(OBu) _m Cl _4-m ; 0<m<4), and phthalates (for example, compounds such as Ph(CO ₂ Bu) _{2.TiCl 4} ), and the like can be used.

1-1-3. Halogen (A1a-3)
Fluorine, chlorine, bromine, iodine, and mixtures thereof can be used as the halogen used in the solid component (A1) according to the present invention. Among these, chlorine is particularly preferred.
Halogen is generally supplied from the above titanium compound and/or magnesium compound, but can also be supplied from other compounds. Typical examples include halogenated silicon compounds typified by silicon tetrachloride, halogenated aluminum compounds typified by aluminum chloride, halogenated organic compounds typified by 1,2-dichloroethane and benzyl chloride, Halogenated borane compounds typified by trichloroborane, halogenated phosphorus compounds typified by phosphorus pentachloride, halogenated tungsten compounds typified by tungsten hexachloride, and halogenated molybdenum compounds typified by molybdenum pentachloride , and so on. These compounds can be used not only singly but also in combination. Among these, silicon tetrachloride is particularly preferred.

1-1-4. Electron donor (A1a-4)
Typical examples of the electron donor (A1a-4) used in the solid component (A1) according to the invention include compounds disclosed in JP-A-2004-124090. In general, organic acids and inorganic acids and their derivatives (esters, acid anhydrides, acid halides, amides) compounds, ether compounds, ketone compounds, aldehyde compounds, alcohol compounds, amine compounds, etc. can be used, It may be one or a mixture of two or more selected from the group consisting of organic acids, inorganic acids, derivative compounds thereof, ether compounds, and ketone compounds.

Organic acid compounds that can be used as the electron donor (A1a-4) include aromatic polycarboxylic acid compounds typified by phthalic acid, aromatic carboxylic acid compounds typified by benzoic acid, 2-n -malonic acid with one or two substituents at the 2-position such as butyl-malonic acid or one or two substituents at the 2-position or the 2- and 3-positions such as 2-n-butyl-succinic acid Aliphatic polyvalent carboxylic acid compounds represented by succinic acid each having one or more substituents, aliphatic carboxylic acid compounds represented by propionic acid, aromatics represented by benzenesulfonic acid and methanesulfonic acid tribal and aliphatic sulfonic acid compounds, and the like.
These carboxylic acid compounds and sulfonic acid compounds, regardless of whether they are aromatic or aliphatic, may have an arbitrary number of unsaturated bonds at arbitrary positions in the molecule like maleic acid.

Examples of organic acid derivative compounds that can be used as the electron donor (A1a-4) include esters (carboxylic acid ester compounds), acid anhydrides, acid halides, and amides of the above organic acids.
Aliphatic and aromatic alcohols can be used as alcohols that are constituents of esters. Among these alcohols, alcohols composed of aliphatic free radicals having 1 to 20 carbon atoms such as ethyl group, butyl group, isobutyl group, heptyl group, octyl group and dodecyl group are preferred. Alcohols comprising aliphatic free radicals having 2 to 12 carbon atoms are more preferred. Alcohols composed of alicyclic free radicals such as cyclopentyl, cyclohexyl and cycloheptyl groups can also be used.

Fluorine, chlorine, bromine, iodine and the like can be used as the halogen which is a constituent of the acid halide. Among them, chlorine is most preferred. In the case of polyhalides of polyvalent organic acids, a plurality of halogens may be the same or different.
Aliphatic and aromatic amines can be used as amines that are constituents of amides. Among these amines, ammonia, aliphatic amines typified by ethylamine and dibutylamine, and amines having aromatic free radicals typified by aniline and benzylamine in the molecule can be exemplified as preferred compounds. .

Examples of inorganic acid compounds that can be used as the electron donor (A1a-4) include carbonic acid, phosphoric acid, silicic acid, sulfuric acid, nitric acid, and the like.
Esters are preferably used as derivative compounds of these inorganic acids. Specific examples include tetraethoxysilane (ethyl silicate), tetrabutoxysilane (butyl silicate), tributyl phosphate, and the like.

Ether compounds that can be used as the electron donor (A1a-4) include aliphatic ether compounds typified by dibutyl ether, aromatic ether compounds typified by diphenyl ether, and 2-isopropyl-2-isobutyl-1. Aliphatic polyhydric ethers represented by 1,3-dimethoxypropane having one or two substituents at the 2-position such as ,3-dimethoxypropane and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane Compounds such as polyvalent ether compounds having aromatic free radicals in the molecule, typified by 9,9-bis(methoxymethyl)fluorene, can be exemplified.

Ketone compounds that can be used as the electron donor (A1a-4) include aliphatic ketone compounds typified by methyl ethyl ketone, aromatic ketone compounds typified by acetophenone, 2,2,4,6,6- Examples include polyvalent ketone compounds typified by pentamethyl-3,5-heptanedione.
Aldehyde compounds that can be used as the electron donor (A1a-4) include aliphatic aldehyde compounds typified by propionaldehyde and aromatic aldehyde compounds typified by benzaldehyde. .
Furthermore, alcohol compounds that can be used as the electron donor (A1a-4) include aliphatic alcohol compounds typified by butanol and 2-ethylhexanol, phenol derivative compounds typified by cresol, glycerin and Aliphatic or aromatic polyhydric alcohol compounds typified by 1,1'-bi-2-naphthol can be exemplified.

Amine compounds that can be used as the electron donor (A1a-4) include aliphatic amine compounds typified by diethylamine, and nitrogen-containing lipids typified by 2,2,6,6-tetramethyl-piperidine. cyclic compounds, aromatic amine compounds typified by aniline, polyvalent amine compounds typified by 1,3-bis(dimethylamino)-2,2-dimethylpropane, nitrogen atom-containing aromatic compounds, etc. can be exemplified.

Further, as a compound that can be used as the electron donor (A1a-4), a compound containing multiple functional groups as described above in the same molecule can also be used. Examples of such compounds include carboxylic acid ester compounds having an alkoxy group in the molecule represented by acetic acid-(2-ethoxyethyl) and ethyl 3-ethoxy-2-t-butylpropionate, 2-benzoyl- Ketoester compounds typified by ethyl benzoate, Ketoether compounds typified by (1-t-butyl-2-methoxyethyl)methylketone, N,N-dimethyl-2,2-dimethyl-3-methoxypropylamine Representative aminoether compounds, halogenoether compounds typified by epoxychloropropane, and the like can be mentioned.

These electron donors (A1a-4) can be used not only alone, but also in combination of multiple compounds.
Among these, preferred are diethyl phthalate, dibutyl phthalate, diisobutyl phthalate, phthalate diester compounds typified by diheptyl phthalate, phthalate dihalide compounds typified by phthaloyl dichloride, and 2-n-butyl- Malonic acid ester compounds having one or two substituents at the 2-position such as diethyl malonate, one or two substituents at the 2-position such as 2-n-butyl-diethyl succinate, or 2 and 3 2-position such as succinic acid ester compounds having one or more substituents at each position, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane and 2-isopropyl-2-isopentyl-1,3-dimethoxypropane Aliphatic polyvalent ether compounds typified by 1,3-dimethoxypropane having one or two substituents in the molecule, aromatic free radicals typified by 9,9-bis (methoxymethyl) fluorene in the molecule and polyvalent ether compounds having
Among these, particularly preferred are organic acid ester compounds, acid halide compounds and ether compounds, and particularly preferred are those selected from the group consisting of phthalic acid diester compounds and phthalic acid dihalide compounds.
The ratio of the amount of each component used in the solid component (A1) used in the present invention may be arbitrary within the range that does not impair the effects of the present invention, but generally the following range is preferable. .

The amount of the titanium compound (A1a-2) used is preferably 0.0001 in terms of molar ratio (number of moles of titanium compound/number of moles of magnesium compound) to the amount of magnesium compound (A1a-1) used. 1,000, preferably 0.001 to 100, and particularly preferably 0.01 to 50.

When a halogen source compound (that is, (A1a-3)) is used in addition to the magnesium compound (A1a-1) and titanium compound (A1a-2), the amount used is such that each of the magnesium compound and titanium compound is halogen. Regardless of whether or not containing the magnesium compound (A1a-1) to be used, the molar ratio (number of moles of halogen source compound / number of moles of magnesium compound) is preferably 0.01 It is in the range of ~1,000, and more preferably in the range of 0.1-100.

The amount of the electron donor (A1a-4) to be used is preferably 0.00 with respect to the amount of the magnesium compound (A1a-1) used, in terms of the molar ratio (number of moles of electron donor/number of moles of magnesium compound). 001 to 10, preferably 0.01 to 5.

The solid component (A1) according to the present invention is obtained by contacting each of the above constituent components in the above quantitative ratio.
As for the contact condition of each component, although it is necessary that oxygen is not present, any condition can be used as long as the effect of the present invention is not impaired. Generally, the following conditions are preferred.
The contact temperature is about -50 to 200°C, preferably 0 to 150°C.
Examples of the contact method include a mechanical method using a rotating ball mill, a vibration mill, and the like, and a method of contact by stirring in the presence of an inert diluent.

During the preparation of the solid component (A1), intermediate and/or final washing with an inert solvent may be carried out.
Preferred solvent species include aliphatic hydrocarbon compounds such as heptane, aromatic hydrocarbon compounds such as toluene and xylene, and halogen-containing hydrocarbon compounds such as 1,2-dichloroethylene and chlorobenzene. .

Any method can be used as the method for preparing the solid component (A1) according to the present invention. Specifically, the methods described in (i) to (vii) below can be exemplified. can. However, the present invention is not limited by the following examples.

(i) Co-grinding method A method of supporting a titanium compound on a magnesium compound by co-grinding a halogen-containing magnesium compound typified by magnesium chloride with a titanium compound. Co-grinding may be performed in the process.
As a mechanical pulverization method, any pulverizer such as a rotary ball mill or a vibrating mill can be used. In addition to the dry pulverization method that does not use a solvent, a wet pulverization method that involves co-pulverization in the presence of an inert solvent can also be used.

(ii) Heat treatment method A contact treatment is performed by stirring a halogen-containing magnesium compound typified by magnesium chloride and a titanium compound in an inert solvent to support a titanium compound on the magnesium compound. The donors may be catalytically treated simultaneously or in separate steps.
When a liquid compound such as titanium tetrachloride is used as the titanium compound, the contact treatment can be carried out without an inert solvent.
In addition, if necessary, an optional component such as a silicon halide compound may be brought into contact at the same time or in a separate step.
Although the contact temperature is not particularly limited, it is often preferable to carry out the contact treatment at a relatively high temperature of about 90°C to 130°C.

(iii) Dissolution-precipitation method In the dissolution-precipitation method, a halogen-containing magnesium compound represented by magnesium chloride is dissolved by contacting it with an electron donor, and the resulting solution is brought into contact with a precipitating agent to cause a precipitation reaction. This is a method for forming particles.
Examples of electron donors used for dissolution include alcohol compounds, epoxy compounds, phosphoric acid ester compounds, silicon compounds having an alkoxy group, titanium compounds having an alkoxy group, and ether compounds. .
Examples of precipitating agents include titanium halide compounds, silicon halide compounds, hydrogen chloride, halogen-containing hydrocarbon compounds, siloxane compounds having Si—H bonds (including polysiloxane compounds), and aluminum. compounds, etc. can be exemplified.
As a method for contacting the dissolving liquid and the precipitating agent, the precipitating agent may be added to the dissolving liquid, or the dissolving liquid may be added to the precipitating agent.
When the titanium compound is not used in either step of dissolution or precipitation, the titanium compound is supported on the magnesium compound by bringing the particles formed by the precipitation reaction into contact with the titanium compound.
Further, if necessary, the particles formed by the above method may be brought into contact with optional components such as halogenated titanium compounds and halogenated silicon compounds, or may be brought into contact with an electron donor. At this time, the electron donor may be different from or the same as that used for dissolution.
The order in which these optional components are brought into contact is not particularly limited, and they may be brought into contact as independent steps, or they may be brought into contact together during dissolution, precipitation, or contact with titanium compounds.
An inert solvent may be present in any of the steps of dissolution, precipitation, and contact with optional components.

(iv) Granulation method In the granulation method, similar to the dissolution precipitation method, a halogen-containing magnesium compound represented by magnesium chloride is brought into contact with an electron donor to dissolve it, and the resulting solution is mainly subjected to physical It is a method of granulating by a general method. Examples of electron donors used for dissolution are the same as those for the dissolution precipitation method.
Examples of granulation techniques include a method of dropping a high-temperature solution into a low-temperature inert solvent, a method of blowing the solution from a nozzle toward the high-temperature gas phase and drying, and a method of drying the solution toward the low-temperature gas phase. and a method of cooling the solution by blowing it out from a nozzle.
The titanium compound is supported on the magnesium compound by bringing the particles formed by granulation into contact with the titanium compound.
Furthermore, if necessary, it may be brought into contact with optional components such as silicon halide compounds and electron donors. At this time, the electron donor may be different from that used for dissolution, or may be the same.
The order in which these optional components are brought into contact is not particularly limited, and they may be brought into contact as independent steps, or they may be brought into contact together during dissolution or contact with the titanium compound.
An inert solvent may be present in any of the steps of dissolution, contact with titanium compounds, and contact with optional components.

(v) Method for Halogenating Magnesium (Mg) Compound A method for halogenating a magnesium (Mg) compound is a method in which a halogen-free magnesium compound is brought into contact with a halogenating agent to be halogenated. may be contact-treated at the same time or in separate steps.
Examples of halogen-free magnesium compounds include dialkoxymagnesium compounds, magnesium oxide, magnesium carbonate, magnesium salts of fatty acids, and the like.
When dialkoxymagnesium compounds are used, those prepared in situ by the reaction of metal magnesium and alcohol can also be used. When this preparation method is used, grains are generally formed by granulation or the like at the stage of a magnesium compound containing no halogen as a starting material.
Examples of halogenating agents include halogenated titanium compounds, halogenated silicon compounds, halogenated phosphorus compounds, and the like.
When halogenated titanium compounds are not used as the halogenating agent, the titanium compound is supported on the magnesium compound by bringing the halogen-containing magnesium compound formed by halogenation into contact with the titanium compound.
Further, if necessary, the particles formed by the above method may be brought into contact with optional components such as halogenated titanium compounds and halogenated silicon compounds, or may be brought into contact with an electron donor.
The order in which these optional components are brought into contact is not particularly limited, and they may be brought into contact as independent steps, or they may be brought into contact together when halogen-free magnesium compounds are halogenated or titanium compounds are brought into contact. can.
In addition, an inert solvent may be present in any of the steps of contacting with the titanium halide compounds and contacting with the optional component.

(vi) Precipitation method from organomagnesium compound A method of bringing a precipitating agent into contact with a solution of an organomagnesium compound such as a Grignard reagent typified by butylmagnesium chloride, a dialkylmagnesium compound, and an electron donor at the same time, or , the contact treatment may be performed in a separate step.
Examples of precipitating agents include titanium compounds, silicon compounds, hydrogen chloride, and the like.
When the titanium compound is not used as the precipitating agent, the titanium compound is supported on the magnesium compound by bringing the particles formed by the precipitation reaction into contact with the titanium compound.
Further, if necessary, the particles formed by the above method may be brought into contact with optional components such as halogenated titanium compounds and halogenated silicon compounds, or may be brought into contact with an electron donor.
The order in which these optional components are brought into contact is not particularly limited, and they may be brought into contact as separate steps, or they may be brought into contact together during precipitation or contact with titanium compounds.
An inert solvent may be present in any of the steps of precipitation, contact with titanium compounds, and contact with optional components.

(vii) Impregnation method This is a method of impregnating an inorganic compound carrier or an organic compound carrier with a solution of an organic magnesium compound or a solution in which a magnesium compound is dissolved in an electron donor.
Examples of organomagnesium compounds are the same as examples of deposition methods from organomagnesium compounds. The magnesium compound used for dissolving the magnesium compound may or may not contain a halogen, and examples of electron donors are the same as those of the dissolution precipitation method.
Examples of inorganic compound carriers include silica, alumina, magnesia, and the like.
Examples of organic compound carriers include polyethylene, polypropylene, polystyrene, and the like.
After the impregnation treatment, the carrier particles precipitate and fix the magnesium compound by a chemical reaction with the precipitating agent or physical treatment such as drying.
Examples of the precipitating agent are the same as those of the dissolution precipitation method.
When the titanium compound is not used as the precipitating agent, the titanium compound is supported on the magnesium compound by further bringing the thus formed particles into contact with the titanium compound. Further, if necessary, the particles thus formed may be brought into contact with optional components such as titanium halide compounds and silicon halide compounds, or may be brought into contact with an electron donor.
The order in which these optional components are brought into contact is not particularly limited, and they may be brought into contact as independent steps, or they may be brought into contact together during impregnation, precipitation, drying, or contact with titanium compounds. An inert solvent may be present in any of the steps of impregnation, precipitation, contact with titanium compounds, and contact with optional components.

(viii) Combined method The methods described in (i) to (vii) above can also be used in combination. Examples of combinations include "a method of co-grinding magnesium chloride with an electron donor and then heat-treating it with a titanium halide compound", and "co-grinding a magnesium chloride compound with an electron donor and then using another electron donor. and then precipitate using a precipitant", "Method of dissolving a dialkoxymagnesium compound with an electron donor and contacting it with a titanium halide compound to precipitate and halogenate the magnesium compound at the same time" , "By contacting a dialkoxymagnesium compound with carbon dioxide, a carbonate magnesium compound is produced and simultaneously dissolved, silica is impregnated with the resulting solution, and then the magnesium compound is halogenated by contacting it with hydrogen chloride. At the same time, it is deposited and immobilized, and further a method of supporting a titanium compound by contacting it with a titanium halide compound.

1-1-5. Prepolymerization of Solid Component (A1) In the method for producing a solid catalyst component for α-olefin polymerization of the present invention, the solid component (A1) is composed of ethylene, propylene, 1-butene, and It may be prepolymerized with at least one olefin selected from the group consisting of 3-methyl-1-butene.

Arbitrary conditions can be used for the reaction conditions of the solid component (A1) and the monomer (olefin) as long as the effects of the present invention are not impaired. Generally, the following range is preferable.
Based on 1 gram of the solid component (A1), the prepolymerized amount of the monomer is in the range of 0.001 to 100 g, preferably 0.1 to 50 g, more preferably 0.5 to 10 g. is desirable.
The reaction temperature during prepolymerization is -150 to 150°C, preferably 0 to 100°C. It is desirable that the reaction temperature during the preliminary polymerization be lower than the polymerization temperature during the main polymerization.
The reaction is generally preferably carried out under stirring, in which case an inert solvent such as hexane, heptane, etc. may be present.
The prepolymerization may be performed multiple times, and the monomers used at this time may be the same or different. Also, washing with an inert solvent such as hexane or heptane can be carried out after the preliminary polymerization.
The material and usage amount of the organoaluminum compound can be the same as those described for the component (A4) to be described later.

1-2. Alkenyl group-containing silicon compound (A2)
Examples of the silicon compound (A2) having an alkenyl group used in the present invention include JP-A-2-34707, JP-A-2003-292522, JP-A-2006-169283, and JP-A-2011-74360. The disclosed compounds and the like can be used.
Generally, it is desirable to use a compound represented by the following general formula.
SiR ¹ _n R ² _4-n
(Here, R ¹ is an alkenyl group, R ² is a hydrogen atom, halogen, an alkyl group or an alkoxy group, and n represents 1 ≤ n ≤ 4. When 1 ≤ n ≤ 2 , R ² may form a cyclic structure linked together.)

In the formula, R ¹ represents an alkenyl group, preferably a vinyl group, an allyl group or a 3-butenyl group, particularly preferably a vinyl group or an allyl group. When the value of n is 2 or more, a plurality of R ¹ may be the same or different.

In the formula, ^R2 represents a hydrogen atom, halogen, alkyl group or alkoxy group.
Examples of halogen that can be used as R ² include fluorine, chlorine, bromine, and iodine.
When R ² is an alkyl group, it is generally an alkyl group having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms. Specific examples of alkyl groups that can be used as R ² include methyl, ethyl, propyl, i-propyl, i-butyl, s-butyl, t-butyl, thexyl and cyclopentyl. groups, cyclohexyl groups, and the like.
When R ² is an alkoxy group, it generally has 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms. Specific examples of alkoxy groups that can be used as R ² include methoxy, ethoxy, propoxy, i-propoxy, i-butoxy, s-butoxy, and t-butoxy groups. desirable. When the value of n is 2 or less, multiple R ² may be the same or different. Further, when 1≦n≦ ² , a ring structure may be formed in which R2s are connected to each other.

Specifically, the silicon compound (A2) having an alkenyl group includes vinylsilane, methylvinylsilane, dimethylvinylsilane, trimethylvinylsilane, trichlorovinylsilane, dichloromethylvinylsilane, chlorodimethylvinylsilane, chloromethylvinylsilane, triethylvinylsilane, chlorodiethylvinylsilane, dichloro ethylvinylsilane, dimethylethylvinylsilane, diethylmethylvinylsilane, tripentylvinylsilane, triphenylvinylsilane, diphenylmethylvinylsilane, dimethylphenylvinylsilane, CH ₂ ═CH—Si(CH ₃ ) ₂ (C ₆ H ₄ CH ₃ ), (CH ₂ ═CH)(CH ₃ ) ₂ Si—O—Si(CH ₃ ) ₂ (CH═CH ₂ ), divinylsilane, dichlorodivinylsilane, dimethyldivinylsilane, diphenyldivinylsilane, allyltrimethylsilane, allyltriethylsilane, allyltri Vinylsilane, allylmethyldivinylsilane, allyldimethylvinylsilane, allylmethyldichlorosilane, allyltrichlorosilane, allyltribromosilane, diallyldimethylsilane, diallyldiethylsilane, diallyldivinylsilane, diallylmethylvinylsilane, diallylmethylchlorosilane, diallyldichlorosilane, diallyl Dibromosilane, triallylmethylsilane, triallylethylsilane, triallylvinylsilane, triallylchlorosilane, triallylbromosilane, tetraallylsilane, di-3-butenyldimethylsilane, di-3-butenylsilane, diethylsilane, di- 3-butenylsilanedivinylsilane, di-3-butenylsilanemethylvinylsilane, di-3-butenylsilanemethylchlorosilane, di-3-butenylsilanedichlorosilane, tri-3-butenylsilaneethylsilane, tri- 3-butenylsilanevinylsilane, tri-3-butenylsilanechlorosilane, tri-3-butenylsilanebromosilane, tetra-3-butenylsilane, 1-methyl-1-vinylsilacyclobutane, 1-methyl-1-vinylsilane Cyclopentane, 1-methyl-1-vinylsilacyclohexane, 1,1-divinylsilacyclopentane, 1,1-divinylsilacyclohexane, 1-chloro-1-vinylsilacyclopentane, 1-chloro-1-vinylsilacyclo Hexane, 1-allyl-1-methylsilacyclopentane , 1-allyl-1-methylsilacyclohexane, and the like.
Among these, vinylsilane compounds are preferred, and trimethylvinylsilane, trichlorovinylsilane, dimethyldivinylsilane, and 1-methyl-1-vinylsilacyclopentane are particularly preferred.

The amount ratio of the alkenyl group-containing silicon compound (A2) to be used may be arbitrary within the range that does not impair the effects of the present invention, but generally the following range is preferred.
The amount of the silicon compound (A2) having an alkenyl group to be used is the molar ratio to the titanium component constituting the solid component (A1) (number of moles of the silicon compound (A2) having an alkenyl group/titanium atom in the solid component (A1) is preferably in the range of 0.001 to 1,000, more preferably in the range of 0.01 to 100.

The alkenyl group-containing silicon compound (A2) used in the present invention generally has greater steric hindrance than α-olefin monomers and cannot be polymerized with a Ziegler-Natta catalyst.
However, due to the presence of organic silyl groups with very strong electron-donating properties, the charge density at the carbon-carbon double bond is extremely high, and coordination with the titanium atom, which is the active center, is extremely difficult. is considered to be faster than
Therefore, by coordinating and complexing the silicon compound having an alkenyl group with the Lewis acid site on the magnesium compound as a carrier, the extraction of the titanium compound into the solvent can be suppressed, and the overreduction of the titanium atom by the organoaluminum compound. It is expected to prevent deactivation of active sites due to impurities and impurities.

1-3. Alkoxysilane compound (A3)
The alkoxysilane compound (A3) used in the method for producing the solid catalyst component (A) for α-olefin polymerization of the present invention is different from the alkenyl group-containing silane compound (A2).
In the method for producing the solid catalyst component (A) for α-olefin polymerization of the present invention, the component (A3) may be a silicon compound represented by the following general formula (1).
R ¹ R ² _m Si(OR ³ ) _n (1)
(wherein R ¹ represents a hydrocarbon group or a heteroatom-containing hydrocarbon group; R ² represents any free radical selected from hydrogen, halogen, hydrocarbon groups and heteroatom-containing hydrocarbon groups; R ³ represents It is a hydrocarbon group and represents 0≦m≦2, 1≦n≦3, and m+n=3.)

In the formula, R ¹ represents a hydrocarbon group or a heteroatom-containing hydrocarbon group.
When R ¹ is a hydrocarbon group, it is a hydrocarbon group other than an alkenyl group.
Hydrocarbon groups that can be used as R ¹ generally have 1 to 20 carbon atoms, preferably 3 to 10 carbon atoms. Specific examples of hydrocarbon groups that can be used as R ¹ include linear aliphatic hydrocarbon groups typified by n-propyl groups, and branched hydrocarbon groups typified by i-propyl groups and t-butyl groups. Examples include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group typified by a cyclopentyl group and a cyclohexyl group, and an aromatic hydrocarbon group typified by a phenyl group. More preferably, R ¹ is a branched aliphatic hydrocarbon group or alicyclic hydrocarbon group, especially i-propyl group, i-butyl group, t-butyl group, thexyl group, cyclopentyl group, It is desirable to use a cyclohexyl group or the like.
Also, when R ¹ is a heteroatom-containing hydrocarbon group, the heteroatom is preferably selected from nitrogen, oxygen, sulfur, phosphorus or silicon, especially nitrogen or oxygen.
The skeleton structure of the heteroatom-containing hydrocarbon group for R ¹ is desirably selected from examples in which R ¹ is a hydrocarbon group. Among them, an N,N-diethylamino group, a quinolino group, an isoquinolino group, and the like are preferred.

Also, in the formula, R ² represents any free radical selected from hydrogen atoms, halogens, hydrocarbon groups and heteroatom-containing hydrocarbon groups.
Examples of halogen that can be used as R ² include fluorine, chlorine, bromine, and iodine.
Also, when R ² is a hydrocarbon group, it is a hydrocarbon group other than an alkenyl group.
Hydrocarbon groups that can be used as R ² generally have 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms. Specific examples of hydrocarbon groups that can be used as R ² include linear aliphatic hydrocarbon groups typified by methyl and ethyl groups, and branched groups typified by i-propyl and t-butyl groups. aliphatic hydrocarbon groups, alicyclic hydrocarbon groups typified by cyclopentyl and cyclohexyl groups, aromatic hydrocarbon groups typified by phenyl groups, and the like. Among them, it is desirable to use methyl group, ethyl group, propyl group, i-propyl group, i-butyl group, s-butyl group, t-butyl group, thexyl group, cyclopentyl group, cyclohexyl group and the like.
Moreover, when R ² is a heteroatom-containing hydrocarbon group, it is desirable to select from the examples of the case where R ¹ is a heteroatom-containing hydrocarbon group. Among them, an N,N-diethylamino group, a quinolino group, an isoquinolino group, and the like are preferred.
Also, regardless of the value of m, R ² may be the same as or different from R ¹ .

Moreover, in the formula, R ³ represents a hydrocarbon group. The hydrocarbon group that can be used as R ³ generally has 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms.
Specific examples of hydrocarbon groups that can be used as R ³ include linear aliphatic hydrocarbon groups typified by methyl and ethyl groups, and branched groups typified by i-propyl and t-butyl groups. aliphatic hydrocarbon groups, and the like. Among them, a methyl group and an ethyl group are most preferred. When the value of n is 2 or more, multiple R ³ may be the same or different.

Preferred examples of the alkoxysilane compound (A3) that can be used in the present invention include t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-butylethyldimethoxysilane, t-butyl-n-propyldimethoxysilane. , cyclohexylmethyldimethoxysilane, cyclohexylethyldimethoxysilane, dicyclopentyldimethoxysilane, diisopropyldimethoxysilane, diisobutyldimethoxysilane, isobutylisopropyldimethoxysilane, n-propylmethyldimethoxysilane, t-butyltriethoxysilane, bis(diethylamino)dimethoxysilane, diethylaminotriethoxysilane methoxysilane, bisperhydroisoquinolinodimethoxysilane, and the like.
These alkoxysilane compounds can not only be used alone, but can also be used in combination with a plurality of compounds.

The amount ratio of the amount of the alkoxysilane compound (A3) to be used may be arbitrary as long as the effects of the present invention are not impaired, but generally the following range is preferred.
The amount of the alkoxysilane compound (A3) used is the molar ratio to the titanium component constituting the solid component (A1) (the number of moles of the alkoxysilane compound (A3)/the number of moles of titanium atoms in the solid component (A1)). It is preferably in the range of 0.01 to 1,000, particularly preferably in the range of 0.1 to 100.

It is believed that the alkoxysilane compound (A3) used in the present invention is coordinated in the vicinity of a titanium atom that can serve as an active site and controls catalytic performance such as the catalytic activity of the active site and the regularity of the polymer. .

1-4. Organoaluminum compound (A4)
As the organoaluminum compound (A4) used in the present invention, compounds disclosed in JP-A-2004-124090 and the like can be used. Generally, it is desirable to use a compound represented by the following general formula.
R ¹ _a AlX _b (OR ² ) _c
(In the formula, R ¹ represents a hydrocarbon group, X represents a halogen or hydrogen atom, R ² represents a hydrocarbon group or a bridging group with Al, a ≥ 1, 0 ≤ b ≤ 2, 0 ≤ c ≤ 2, a+b+c=3.)
In the formula, R ¹ is a hydrocarbon group, preferably having 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, particularly preferably 1 to 6 carbon atoms. Specific examples of R ¹ include methyl group, ethyl group, propyl group, butyl group, isobutyl group, hexyl group and octyl group. Among these, methyl group, ethyl group and isobutyl group are most preferred.
In formula, X is a halogen or a hydrogen atom. Halogen that can be used as X includes fluorine, chlorine, bromine, and iodine. Among these, chlorine is particularly preferred.
In the formula, R ² is a hydrocarbon group or a bridging group with Al. ^When R ² is a hydrocarbon group, it can be selected from the same group of hydrocarbon groups exemplified for R ¹ . Alumoxane compounds typified by methylalumoxane can also be used as the organoaluminum compound (A4), in which case R ² represents a cross-linking group with Al.

Examples of compounds that can be used as the organoaluminum compound (A4) include trimethylaluminum, triethylaluminum, triisobutylaluminum, trioctylaluminum, diethylaluminum chloride, ethylaluminum chloride, diethylaluminum ethoxide, methylalumoxane, and the like. can be mentioned.
Among them, triethylaluminum and triisobutylaluminum are preferred.
The organoaluminum compound (A4) can be used not only as a single compound, but also as a combination of multiple compounds.

The amount ratio of the amount of the organoaluminum compound (A4) to be used may be arbitrary as long as the effects of the present invention are not impaired, but generally the following range is preferred.
The amount of the organoaluminum compound (A4) to be used is preferably 0.1 in terms of the molar ratio to the titanium component constituting the solid component (A1) (the number of moles of aluminum atoms/the number of moles of titanium atoms in the solid component (A1)). It is in the range of 1 to 100, particularly preferably in the range of 1 to 50.

The organoaluminum compound (A4) used in the present invention is used for the purpose of efficiently supporting the alkoxysilane compound (A3) on the solid catalyst component (A) for α-olefin polymerization.
Therefore, it is distinguished from the organoaluminum compound (B) used as a co-catalyst during the main polymerization described later because of its different purpose of use.

1-5. Compound (A5) having at least two ether bonds
The α-olefin polymerization solid catalyst component (A) obtained by the production method of the present invention comprises a silicon compound having an alkenyl group (A2), an alkoxysilane compound (A3) and an organic Although the aluminum compound (A4) is brought into contact, a compound (A5) having at least two ether bonds may be brought into contact as an optional component within a range that does not impair the effects of the present invention.
As the compound (A5) having at least two ether bonds that can be used in the present invention, compounds disclosed in JP-A-3-294302 and JP-A-8-333413 can be used. Generally, it is desirable to use a compound represented by the following formula.
R ³ O—C(R ² ) ₂ —C(R ¹ ) ₂ —C(R ² )—OR ³
(wherein R ¹ and R ² represent any free radical selected from a hydrogen atom, a hydrocarbon group or a heteroatom-containing hydrocarbon group; R ³ represents a hydrocarbon group or a heteroatom-containing hydrocarbon group .)
Specific examples of the compound (A5) having at least two ether bonds include 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2-isobutyl- 2-isopropyl-1,3-dimethoxypropane, 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, 2,2-dicyclopentyl-1,3-dimethoxypropane, 9,9-bis(methoxymethyl)fluorene etc.
Moreover, the compound (A5) having at least two ether bonds can be used not only alone, but also in combination of multiple compounds. Further, it may be the same as or different from the polyvalent ether compound used as the electron donor (A1a-4), which is an essential component in the solid component (A1).

The ratio of the amount of the compound (A5) having at least two ether bonds to be used may be arbitrary within the range that does not impair the effects of the present invention, but is generally preferably within the following range.
The amount of the compound (A5) having at least two ether bonds used is the molar ratio to the titanium component constituting the solid component (A1) (the number of moles of the compound (A5) having at least two ether bonds/solid component (A1) The number of moles of titanium atoms therein) is preferably in the range of 0.01 to 10,000, particularly preferably in the range of 0.5 to 500.

1-6. Method for preparing solid catalyst component for α-olefin polymerization (A) In the production method of the present invention, when preparing the solid catalyst component for α-olefin polymerization (A), an alkenyl group is added to the solid component (A1). A silicon compound (A2), an alkoxysilane compound (A3), and an organoaluminum compound (A4) having a are contact-treated at a temperature of 50 to 110°C.
In the production method of the present invention, the contact treatment may be carried out multiple times during the preparation of the α-olefin polymerization solid catalyst component (A).
When the contact treatment is performed multiple times, the silicon compound (A2) having an alkenyl group, the alkoxysilane compound (A3), and the organoaluminum compound (A4) are all the same compounds used in multiple contacts. may be different.
The solid catalyst component (A) for α-olefin polymerization of the present invention is obtained by contacting each of the above constituent components in the above quantitative ratio.
In addition, although the range of the amount of each component used was shown above, this is the amount used for one contact, and from the second time onwards, if the amount used is within the range of the amount used above, , can be contacted any number of times.

The conditions for contacting each constituent component of the solid catalyst component (A) for α-olefin polymerization must be in the absence of oxygen, but any conditions can be used as long as the effects of the present invention are not impaired. Generally, the following conditions are preferred.

Examples of the contact method include a mechanical method using a rotating ball mill, a vibration mill, and the like, and a method of contact by stirring in the presence of an inert diluent. Preferably, it is desirable to use a method of contacting by stirring in the presence of an inert diluent.
If the contact temperature is too low, the reaction does not proceed and a large amount of the electron donor (A1a-4) remains, possibly deteriorating catalytic performance such as stereoregularity. On the other hand, if the contact temperature is too high, the active sites themselves may be altered, which may significantly deteriorate catalytic performance such as activity and stereoregularity. The contact temperature may be 50 to 110°C, 50 to 100°C, 50 to 95°C, 60 to 90°C, or 70 to 90°C. good.

In the contact treatment, any procedure can be used for contacting the solid component (A1), the silicon compound (A2) having an alkenyl group, the alkoxysilane compound (A3), and the organoaluminum compound (A4). Specific examples include the following procedures (i) to (iv), among which procedures (i) and (ii) are preferred.
Procedure (i): A method of contacting a solid component (A1) with a silicon compound (A2) having an alkenyl group, then with an alkoxysilane compound (A3), and then with an organoaluminum compound (A4).
Procedure (ii): A method of contacting the solid component (A1) with the silicon compound (A2) having an alkenyl group and the alkoxysilane compound (A3), and then contacting the organoaluminum compound (A4).
Procedure (iii): A method of contacting the solid component (A1) with the alkoxysilane compound (A3), then with the silicon compound (A2) having an alkenyl group, and then with the organoaluminum compound (A4).
Procedure (iv): Method of contacting all compounds simultaneously.
When the compound (A5) having at least two ether bonds is used as an optional component, they can be contacted in any order as described above.

During the preparation of the α-olefin polymerization catalyst component (A), intermediate and/or final washing with an inert solvent may be carried out. Preferred solvents for washing include aliphatic hydrocarbon compounds such as heptane, aromatic hydrocarbon compounds such as toluene and xylene, and halogen-containing hydrocarbon compounds such as 1,2-dichloroethylene and chlorobenzene. can be done.

1-7. Prepolymerization of solid catalyst component for α-olefin polymerization (A) The solid catalyst component for α-olefin polymerization (A) obtained by the production method of the present invention may be prepolymerized before being used in the main polymerization. . By forming a small amount of polymer around the catalyst prior to the polymerization process, the catalyst becomes more uniform and the generation of fines can be suppressed.
A compound disclosed in JP-A-2004-124090 or the like can be used as the monomer in the preliminary polymerization.
Specific examples of compounds include olefins represented by ethylene, propylene, 1-butene, 3-methylbutene-1, 4-methylpentene-1, styrene, α-methylstyrene, allylbenzene, chlorostyrene. , and styrene-like compounds represented by 1,3-butadiene, isoprene, 1,3-pentadiene, 1,5-hexadiene, 2,6-octadiene, dicyclopentadiene, 1,3-cyclohexadiene, 1 , 9-decadiene, divinylbenzenes, and diene compounds represented by the like.
Among them, ethylene, propylene, 3-methylbutene-1, 4-methylpentene-1, styrene, divinylbenzenes, and the like are particularly preferred.

When a prepolymerized solid catalyst component (A) for α-olefin polymerization is used, prepolymerization can be carried out by any procedure in the preparation procedure. For example, the components (A2 to A4) can be contacted after prepolymerizing the α-olefin polymerization solid catalyst component (A). Furthermore, prepolymerization may be carried out at the same time when the solid catalyst component (A) for α-olefin polymerization and the components (A2 to A4) are brought into contact with each other.

Any conditions can be used as the reaction conditions for the solid catalyst component (A) for α-olefin polymerization and the above monomers as long as the effects of the present invention are not impaired. Generally, the following range is preferable.
Based on 1 gram of the solid catalyst component for α-olefin polymerization (A), the prepolymerized amount of the monomer is in the range of 0.001 to 100 g, preferably 0.1 to 50 g, more preferably 0.00 g. A range of 5 to 10 g is desirable.
The reaction temperature during prepolymerization is -150 to 150°C, preferably 0 to 100°C. It is desirable that the reaction temperature during the preliminary polymerization be lower than the polymerization temperature during the main polymerization.
The reaction is generally preferably carried out under stirring, in which case an inert solvent such as hexane, heptane, etc. may be present.
The prepolymerization may be performed multiple times, and the monomers used at this time may be the same or different. Also, washing with an inert solvent such as hexane or heptane can be carried out after the preliminary polymerization.

1-8. Solid catalyst component for α-olefin polymerization (A)
The α-olefin polymerization solid catalyst component (A) obtained by the production method of the present invention includes magnesium (A1a-1), titanium (A1a-2), halogen (A1a-3), and electron donor (A1a-4). and an alkoxysilane compound (A3).
Magnesium (A1a-1), titanium (A1a-2), halogen (A1a-3), electron donor (A1a-4) and alkoxysilane compound (A3) contained in solid catalyst component (A) for α-olefin polymerization Since the materials of are as described above, their description is omitted here.

The content of the electron donor (A1a-4) in the solid catalyst component for α-olefin polymerization (A) may be 40 μmol or less, preferably 37 μmol or less per unit mass of the solid catalyst component for α-olefin polymerization (A). is preferably
If the electron donor (A1a-4) remains in the solid catalyst component (A) for α-olefin polymerization, it is thought that catalytic performance such as stereoregularity may be deteriorated. - As the lower limit of the content of the electron donor (A1a-4) in the solid catalyst component for olefin polymerization (A), is it all removed after preparation of the catalyst component for α-olefin polymerization (A) and is 0? , is preferably as close to 0 as possible.

2. α-Olefin Polymerization Catalyst The α-olefin polymerization catalyst of the present invention is characterized by comprising the solid catalyst component (A) for α-olefin polymerization obtained by the production method described above and the following component (B).
Component (B): Organoaluminum compound

2-1. Organoaluminum compound (B)
As the organoaluminum compound (B) that can be used in the present invention, compounds disclosed in JP-A-2004-124090 can be used.
Preferably, it can be selected from the same group as exemplified for the organoaluminum compound (A4) which is a component when preparing the solid catalyst component (A) for α-olefin polymerization.
The organoaluminum compound (B) that can be used in the α-olefin polymerization catalyst is the same as the organoaluminum compound (A4) that can be used in preparing the solid catalyst component (A) for α-olefin polymerization. may be different.
As the organoaluminum compound (B), not only a single compound but also a plurality of compounds can be used in combination.
The amount of the organoaluminum compound (B) used is determined by the molar ratio to the titanium component constituting the α-olefin polymerization solid catalyst component (A) (the number of moles of the organoaluminum compound (B)/the solid catalyst component for α-olefin polymerization ( The number of moles of titanium atoms in A) is preferably in the range of 1 to 5,000, particularly preferably in the range of 10 to 500.

2-2. Organosilicon compound (C)
In the present invention, the α-olefin polymerization catalyst may contain optional components such as an organosilicon compound (C) and a compound (D) having at least two ether bonds within a range that does not impair the effects of the present invention. good.
As the organosilicon compound (C) used as an optional component in the α-olefin polymerization catalyst of the present invention, compounds disclosed in JP-A-2004-124090 and the like can be used. Preferably, it can be selected from the same group as exemplified for the alkoxysilane compound (A3) which is a component when preparing the solid catalyst component (A) for α-olefin polymerization.
Also, the organosilicon compound (C) used here may be the same as or different from the alkoxysilane compound (A3) contained in the solid catalyst component for α-olefin polymerization (A).
Furthermore, when the organosilicon compound (C) is used, the amount used is the molar ratio to the titanium component constituting the solid catalyst component (A) for α-olefin polymerization (the number of moles of the organosilicon compound (C)/α-olefin polymerization The number of moles of titanium atoms in the solid catalyst component (A) for use) is preferably in the range of 0.01 to 10,000, particularly preferably in the range of 0.5 to 500.

2-3. Compound (D) having at least two ether bonds
In the α-olefin polymerization catalyst according to the present invention, the compound (D) having at least two ether bonds used as an optional component is disclosed in JP-A-3-294302 and JP-A-8-333413. A compound or the like can be used.
Preferably, it can be selected from the same group as exemplified for the compound (A5) having at least two ether bonds used in the solid catalyst component (A) for α-olefin polymerization. At this time, a compound (A5) having at least two ether bonds used as an optional component in preparing the solid catalyst component (A) for α-olefin polymerization, and at least a compound (A5) used as an optional component for the α-olefin polymerization catalyst The compounds (D) having two ether bonds may be the same or different.
As the compound (D) having at least two ether bonds, not only a single compound can be used, but also multiple compounds can be used in combination.
When using the compound (D) having at least two ether bonds, the amount used is the molar ratio to the titanium component constituting the solid catalyst component (A) for α-olefin polymerization (the compound (D) having at least two ether bonds number of moles/number of moles of titanium atoms in solid catalyst component (A) for α-olefin polymerization), preferably in the range of 0.01 to 10,000, particularly preferably in the range of 0.5 to 500. Inside is preferred.

2-4. Other compounds Components other than the organosilicon compound (C) and the compound (D) having at least two ether bonds are used as optional components of the α-olefin polymerization catalyst unless the effects of the present invention are impaired. be able to. For example, the compound (E) having a C(=O)N bond in the molecule disclosed in JP-A-2004-124090 and the sulfite ester compound (F) disclosed in JP-A-2006-225449 are By using it, the generation of amorphous components such as CXS can be suppressed. In this case, tetramethylurea, 1,3-dimethyl-2-imidazolidinone, 1-ethyl-2-pyrrolidinone, dimethyl sulfite, diethyl sulfite and the like can be mentioned as preferred examples.
Also, as disclosed in JP-A-8-66710, an organometallic compound having metal atoms other than Al, such as diethylzinc (G), can be used.
When using the compound (E) having a C(=O)N bond in the molecule, the sulfite compound (F) and the diethylzinc (G), the amount used constitutes the solid catalyst component for α-olefin polymerization (A). The molar ratio to the titanium component (number of moles of optional components (E), (F), and (G)/number of moles of titanium atoms in the solid catalyst component for α-olefin polymerization (A)) is preferably 0.001. It is in the range of 1,000 to 1,000, and more preferably in the range of 0.05 to 500.

3. Method for Producing α-Olefin Polymer The method for producing an α-olefin polymer of the present invention is characterized by homopolymerizing or copolymerizing an α-olefin using the α-olefin polymerization catalyst.

3-1. Polymerization of α-Olefins The catalyst for α-olefin polymerization of the present invention is used.
Polymerization of the α-olefin may be carried out by slurry polymerization using a hydrocarbon solvent, liquid-phase solventless polymerization that does not substantially use a solvent, gas-phase polymerization, or the like.
Hydrocarbon solvents such as pentane, hexane, heptane and cyclohexane are used as the polymerization solvent in slurry polymerization.
The polymerization method employed may be any method such as continuous polymerization, batch polymerization or multistage polymerization.
The polymerization temperature is usually about 30 to 200° C., preferably 50 to 150° C. At that time, hydrogen may be used as a molecular weight modifier.

3-2. α-Olefin Monomer Raw Material In the present invention, the α-olefin is represented by the following general formula.
R-CH= _CH2
(In the formula, R is a hydrocarbon group having 1 to 20 carbon atoms and may have a branched group.)
Specific examples are α-olefins such as propylene, butene-1, pentene-1, hexene-1, and 4-methylpentene-1. In addition to homopolymerization of these α-olefins, random copolymerization of α-olefins with copolymerizable monomers (eg, ethylene, α-olefins, dienes, styrenes, etc.) can also be carried out.
Block copolymerization can also be carried out in which random copolymerization is performed in the second stage after homopolymerization in the first stage.
Copolymerizable monomers can be used up to 15% by weight in random copolymerization and up to 50% by weight in block copolymerization.
Among them, homopolymerization and block copolymerization of α-olefins are preferred, and homopolymerization of propylene and block copolymerization in which the first stage is homopolymerization of propylene are most preferred.

The index of the α-olefin polymer polymerized according to the present invention is not particularly limited, and can be appropriately adjusted according to various uses.
In general, the MFR of the α-olefin polymer is preferably within the range of 0.01 to 10,000 g/10 min, particularly preferably within the range of 0.1 to 1,000 g/10 min. be.

The α-olefin polymer obtained by the production method of the present invention preferably has high stereoregularity.
The stereoregularity of polypropylene is shown here. The stereoregularity of polypropylene can be evaluated by ¹³ C-NMR.
Preferred are those having stereoregularity in which the mm fraction of 3 chains of propylene units obtained by ¹³ C-NMR is 96.0% or more.
The mm fraction is the ratio of 3 chains of propylene units having the same methyl branch direction in each propylene unit among arbitrary 3 chains of propylene units consisting of head-to-tail bonds in the polymer chain, and the upper limit is 100%. be.
This mm fraction is a value indicating that the steric structure of the methyl groups in the polypropylene molecular chain is isotactically controlled, and the higher the value, the more highly controlled it is.
By setting the mm fraction within the range shown below, the flexural modulus, which is an index of the rigidity of the propylene polymer, can be increased.
That is, when the mm fraction is smaller than the value shown below, the mechanical properties tend to be deteriorated, such as the flexural modulus, which is an index of the rigidity of the propylene polymer.
Therefore, the mm fraction of the propylene polymer obtained by the production method of the present invention is preferably 96.0% or more, more preferably 97.0% or more, and the upper limit is 100% as described above.

The mm fraction of propylene unit triplets can be calculated using the ¹³ C-NMR spectrum.
Spectra can be assigned with reference to Polymer Journal, Vol. 16, p. 717 (1984), Macromolecules, Vol. 8, p. 687 (1975), and Polymer, Vol. 30, p. 1350 (1989).
A more specific method for determining the mm fraction is shown below.
The signals originating from the methyl group of the central propylene of the 3 chains head-to-tail linked around the propylene unit occur in 3 regions depending on the configuration.
mm: about 24.0 to about 21.1 ppm
mr+rm: about 21.1 to about 20.4 ppm
rr: about 20.4 to about 19.7 ppm
The chemical shift range of each region slightly shifts depending on the molecular weight and copolymer composition, but the above three regions can be easily identified.
Here, mm, mr+rm and rr are represented by structural formulas 1-(a) to 1-(c) below, respectively.

In addition, the terminal structure may have the following structural formulas 2-(a) to 2-(d).

Among them, carbon A1, A1′, and C2 signals appeared in the mm region, carbon A4′, B4′, C5′, and D3 signals in the mr region, and carbon B2 signal in the rr region, and were linked head-to-tail. It is a signal that is not based on 3 linkages. Therefore, when calculating the mm fraction, from the signal area of the mm region, the signal area of the mr region, and the signal area of the rr region, carbon A1, A1', A4', B4', B2, C2, C5' , D3 should be reduced.
The signal area based on carbon A1, the signal area based on carbon A1', and the signal area based on carbon A4' can be evaluated from the signal area of carbon A2 (resonance around 25.7 ppm) in structural formula 2-(a).
The signal area based on carbon B2 and the signal area based on carbon B4' are the sum of the signal areas of carbon B1 (resonance near 14.4 ppm) and carbon B3 (resonance near 39.6 ppm) in structural formula 2-(b). can be evaluated from 1/2 of
The signal area based on carbon C2 and the signal area based on carbon C5' can be evaluated from carbon C1 (resonance around 14.1 ppm) in structural formula 2-(c).
The signal area based on carbon D3 can be evaluated from half the sum of the signal areas of carbon D5 (resonance around 16.2 ppm) and carbon D2 (resonance around 31.8 ppm) in structural formula 2-(d).

The mm fraction is calculated from the following formula (I).
mm fraction (%) = I _mm × 100/(I _mm + I _{mr + rm} + I _rr ) (I)
[In the above formula (I), I _mm , I _mr+rm , and I _rr are as follows.
I _rr (signal intensity in rr region)=I _20.4-19.7 −(I _14.5-14.4 +I _39.7-39.5 )/2
I _{mr + rm} (signal intensity of mr region) = I _21.1-20.4 - (I _14.5-14.4 + I _39.7-39.5 )/2-I _{25.8-25.7 -} I _{14.1 ~ 14.0} - (I _{16.2 ~ 16.1} + I _{31.9 ~ 31.8} ) / 2
I _CH3 (signal intensity of _CH3 region)=I _24.0-19.7
I _mm (signal intensity in mm area)=I _CH3 − I _mr+rm − I _rr −2×I _25.8-25.7 −I _14.1-14.0 ]

The α-olefin polymer polymerized by the present invention is characterized in that it contains an extremely small amount of amorphous components, has high stereoregularity, and has good odor and color.
The cold xylene solubles (CXS), which is the amorphous component of the α-olefin polymer, generally has a different preferred range depending on the application. For example, in applications where hard moldings are preferred, such as general injection applications, in the case of polypropylene, the cold xylene solubles (CXS) preferably has an upper limit of 1.2% by mass or less and a lower limit of 0.1%. It is at least 0.2% by mass, more preferably at least 0.2% by mass.
Moreover, the polymer particles obtained by the present invention exhibit excellent particle properties. In general, the particle properties of polymer particles are evaluated by polymer bulk density, particle size distribution, particle appearance, and the like.
The polymer particles obtained by the present invention have a polymer bulk density within the range of 0.35-0.55 g/ml, preferably within the range of 0.40-0.50 g/ml.

The α-olefin polymer polymerized by the present invention has an extremely small amount of amorphous components and high stereoregularity, and therefore has high density, high rigidity and high heat resistance, and has excellent properties.
In addition, this α-olefin polymer is produced at a high yield, and is particularly suitable for industrial materials such as automobile parts and home appliance parts that require high rigidity and high heat resistance, and packaging materials because it is less sticky. It can be suitably used for the purpose of

Next, the present invention will be specifically described with reference to examples, but the present invention is not restricted by these examples unless it deviates from the gist thereof. In addition, the measuring method in the present example is as follows.

(Various physical property measurement methods)
(1) Titanium content:
Samples were accurately weighed, hydrolyzed and measured using a colorimetric method. For the prepolymerized sample, the content was calculated using the mass excluding the prepolymerized polymer.

(2) Phthalate content:
After accurately weighing the sample and decomposing the sample with sulfuric acid, the phthalates were extracted into heptane. The phthalate ester concentration in the resulting heptane solution was determined by comparison with a standard sample using gas chromatography. The phthalate content in the sample was calculated from the phthalate concentration in heptane and the mass of the sample. For the prepolymerized sample, the content was calculated using the mass excluding the prepolymerized polymer.

(3) Alkoxysilane compound content:
Samples were accurately weighed and digested with methanol. The silicon compound concentration in the resulting methanol solution was determined by comparison with a standard sample using gas chromatography. The silicon compound content in the sample was calculated from the silicon compound concentration in methanol and the mass of the sample. For the prepolymerized sample, the content was calculated using the mass excluding the prepolymerized polymer.

(4) Polymer bulk density:
The bulk density of powder samples was measured using an apparatus according to ASTM D1895-69.

(5) MFR:
Using a melt indexer manufactured by Takara Co., Ltd., evaluation was performed under conditions of 230° C. and 21.18 N based on JIS-K6921.

(6) 23° C. xylene soluble component amount (CXS: mass %):
The sample (approximately 5 g) was completely dissolved once in p-xylene (300 ml) at 140°C.
After that, it was cooled to 23°C, and the polymer was precipitated at 23°C for 12 hours. After filtering off the precipitated polymer, p-xylene was evaporated from the filtrate. The polymer remaining after evaporating the p-xylene was vacuum dried at 100° C. for 2 hours. The polymer after drying was weighed to give the CXS value as a weight percent of the sample.

(7) mm fraction (three chains of propylene units):
The mm fraction of propylene unit triplets was calculated using the ¹³ C-NMR spectrum.
¹³ C-NMR measurement conditions:
[Sample preparation and measurement conditions]
200 mg of a sample was combined with 2.4 ml of o-dichlorobenzene/deuterobrominated benzene (C ₆ D ₅ Br) = 4/1 (volume ratio) and hexamethyldisiloxane as a chemical shift reference substance. It was placed in an NMR sample tube with an inner diameter of 10 mmφ, replaced with nitrogen, sealed, and uniformly melted with a block heater at 150°C.
For NMR measurement, an AV400 type NMR apparatus (Bruker Biospin Co., Ltd.) equipped with a 10 mmφ cryoprobe was used.
The measurement conditions of ¹³ C-NMR were a sample temperature of 120° C., a pulse angle of 90°, a pulse interval of 15 seconds, and an accumulation number of 512 times, and measurement was performed by a broadband decoupling method.
The chemical shift was set to 1.98 ppm for the ¹³ C signal of hexamethyldisiloxane and the chemical shifts of the other ¹³ C signals were referenced to this.

( Reference example 1)
[Preparation of solid component (A1)]
A 10 L capacity autoclave equipped with a stirrer was sufficiently purged with nitrogen and 2 L of purified toluene was introduced.
Here, 200 g of Mg(OEt) ₂ as a magnesium source and 1 L of TiCl ₄ as a titanium source were added at room temperature.
The temperature was raised to 90° C. and 50 ml of di-n-butyl phthalate as an electron donor were introduced.
After that, the temperature was raised to 110° C. and the reaction was carried out for 3 hours.
Then, the reaction product was thoroughly washed with purified toluene.
Next, refined toluene was introduced to adjust the total liquid volume to 2 L.
After that, 1 L of TiCl ₄ was added at room temperature, and the temperature was raised to 110° C. to carry out the reaction for 2 hours.
Then, the reaction product was thoroughly washed with purified toluene.
Next, purified toluene was introduced to adjust the total liquid volume to 2 L.
After that, 1 L of TiCl ₄ was added at room temperature, and the temperature was raised to 110° C. to carry out the reaction for 2 hours.
Then, the reaction product was thoroughly washed with purified toluene. Furthermore, purified n-heptane was used to replace toluene with n-heptane to obtain a slurry of solid component (A1).

[Preparation of solid catalyst component (A) for α-olefin polymerization]
A 20 L capacity autoclave equipped with a stirring device was sufficiently purged with nitrogen, and 100 g of the solid component (A1) slurry was introduced as the solid component (A1).
(Contact treatment)
Purified n-heptane was introduced to adjust the liquid level to 4L.
Here, 50 ml of dimethyldivinylsilane as the component (A2), 40 ml of t-Bu(Me)Si(OMe) ₂ as the component (A3), and an Et ₃ diluted solution of Et ₃ Al in n-heptane as the component (A4). 80 g of Al was added and reacted at 70° C. for 2 hours.
(Washing)
After that, the reaction product was sufficiently washed with purified n-heptane and vacuum-dried to obtain a solid catalyst component (A) for α-olefin polymerization.

[Preliminary polymerization]
Using the solid catalyst component for α-olefin polymerization (A) obtained above, prepolymerization was carried out according to the following procedure.
Refined n-heptane was introduced into the solid catalyst component (A) for α-olefin polymerization to adjust the concentration of the solid catalyst component (A) for α-olefin polymerization to 20 g/L.
After cooling the slurry to 10° C., 10 g of Et _{3 Al diluted in n-heptane of Et 3 Al} was added as component (A4), and 210 g of propylene was supplied over 4 hours.
After the propylene supply was finished, the reaction was continued for an additional 30 minutes.
Then, the gas phase was sufficiently purged with nitrogen, and the reaction product was thoroughly washed with purified n-heptane.
The resulting slurry was taken out from the autoclave and vacuum dried to obtain a prepolymerized solid catalyst component (A) for α-olefin polymerization.
After the prepolymerization, the α-olefin polymerization solid catalyst component (A) contained 2.0 g of polypropylene per 1 g.
As a result of analysis, the portion of the α-olefin polymerization solid catalyst component (A) after prepolymerization excluding polypropylene contained 288 μmol/g of Ti and 37 μmol/g of di-n-butyl phthalate as an electron donor. g, 230 μmol/g of t-Bu(Me)Si(OMe) ₂ was contained as component (A3). Table 1 shows the results.

[Polymerization of propylene]
A stainless steel autoclave with an inner volume of 3.0 liters equipped with a stirrer and temperature controller was dried by heating under vacuum, cooled to room temperature and replaced with propylene.
After that, 550 milligrams of Et ₃ Al and 2000 milliliters of hydrogen were introduced as component (B).
1000 grams of liquid propylene was then introduced and the internal temperature was adjusted to 70°C.
Thereafter, 7 mg of the prepolymerized α-olefin polymerization catalyst component (A) was injected to polymerize propylene.
After 1 hour, 10 ml of ethanol was pressurized to terminate the polymerization.
The polymer was dried and weighed. Table 1 shows the results.

( Reference example 2)
Components (A1), (A2), (A3) and (A4) were treated in the same manner as in Reference Example 1 except that the contact treatment was carried out at 90°C.
The portion of the solid catalyst component (A) for α-olefin polymerization after prepolymerization excluding polypropylene contained 253 μmol/g of Ti, 10 μmol/g of di-n-butyl phthalate as an electron donor, and component (A3). t-Bu(Me)Si(OMe) ₂ was contained at 350 μmol/g as Table 1 shows the results.

(Comparative example 1)
[Preparation of solid component (A1)]
As the solid component (A1), the solid component (A1) described in Comparative Example 1 of JP-A-2008-163151 was used.
[Preparation of solid catalyst component (A) for α-olefin polymerization, prepolymerization, polymerization of propylene]
Then, in the same manner as in Reference Example 1 of the present specification, except that the contact treatment of components (A1), (A2), (A3) and (A4) was performed at 40 ° C. in Reference Example 1 of the present specification. gone.
The portion of the solid catalyst component (A) for α-olefin polymerization after prepolymerization excluding polypropylene contained 334 μmol/g of Ti, 123 μmol/g of di-n-butyl phthalate as an electron donor, and component (A3). t-Bu(Me)Si(OMe) ₂ was contained at 234 μmol/g as Table 1 shows the results.

(Comparative example 2)
In Reference Example 1, the solvent used in [Preparation of α-olefin polymerization solid catalyst component (A)] was changed from n-heptane to xylene, and components (A1), (A2), (A3) and (A4) were prepared. It was carried out in the same manner as in Reference Example 1 of the present specification, except that the contact treatment was carried out at 130°C.
The portion of the solid catalyst component (A) for α-olefin polymerization after prepolymerization excluding polypropylene contained 196 μmol/g of Ti, 1 μmol/g of di-n-butyl phthalate as an electron donor, and component (A3). t-Bu(Me)Si(OMe) ₂ was contained at 170 μmol/g as Table 1 shows the results.

(Example 3)
[Preliminary polymerization of solid component (A1)]
A 20 L capacity autoclave equipped with a stirring device was sufficiently purged with nitrogen, and 200 g of a slurry of the solid component (A1) of Reference Example 1 was introduced as the solid component (A1).
Purified n-heptane was introduced to adjust the concentration of the solid component (A1) to 25 g/L.
After cooling the slurry to 10° C., 20 g of Et _{3 Al diluted in n-heptane of Et 3 Al} was added as component (A4), and 420 g of propylene was supplied over 4 hours.
After the propylene supply was finished, the reaction was continued for an additional 30 minutes.
Then, the gas phase was sufficiently purged with nitrogen, and the reaction product was thoroughly washed with purified n-heptane to obtain a solid component (A1') as a prepolymerized solid component (A1).
[Preparation of solid catalyst component (A) for α-olefin polymerization]
(Contact treatment)
Thereafter, purified n-heptane was introduced to adjust the liquid level to 4L. Here, 50 ml of dimethyldivinylsilane as component (A2), 40 ml of t-Bu(Me)Si(OMe) ₂ as component (A3), and Et ₃ of n-heptane diluted solution of Et ₃ Al as component (A4). 80 g of Al was added and reacted at 70° C. for 2 hours.
(Washing)
The reaction product was thoroughly washed with purified n-heptane.
A portion of the resulting slurry was sampled and dried.
The resulting slurry was extracted from the autoclave and vacuum dried to obtain a solid catalyst component (A) for α-olefin polymerization.
This α-olefin polymerization solid catalyst component (A) contained 2.1 g of polypropylene per 1 g. Analysis revealed that the portion of the solid catalyst component (A) for α-olefin polymerization excluding polypropylene contained 278 μmol/g of Ti, 28 μmol/g of di-n-butyl phthalate as an electron donor, and component (A3 ) contained 425 μmol/g of t-Bu(Me)Si(OMe) ₂ .
[Polymerization of propylene]
Propylene polymerization was carried out in the same manner as in Reference Example 1. Table 1 shows the results.

(Example 4)
The procedure of Example 3 was repeated except that the contact treatment of components (A1'), (A2), (A3) and (A4) was carried out at 90°C.
The solid catalyst component for α-olefin polymerization (A) contains 244 µmol/g of Ti, 5 µmol/g of di-n-butyl phthalate as an electron donor, and t-Bu(Me)Si(OMe) as component (A3). ₂ was present at 484 μmol/g. Table 1 shows the results.

(Comparative Example 3)
[Preparation of solid component (A1′)]
As the solid component (A1′), the solid component (A1′) described in Example 1 of JP-A-2008-163151 was used.
[Preparation of solid catalyst component (A) for α-olefin polymerization, prepolymerization, polymerization of propylene]
Then, in the same manner as in Example 3 of this specification, except that the contact treatment of components (A1′), (A2), (A3) and (A4) in Example 3 of this specification was performed at 40 ° C. gone.
355 µmol/g of Ti in the α-olefin polymerization solid catalyst component (A), 105 µmol/g of di-n-butyl phthalate as an electron donor, and t-Bu(Me)Si(OMe) as component (A3). ₂ was present at 456 μmol/g. Table 1 shows the results.

As is clear from Table 1, a comparative study of Examples and Comparative Examples shows that the α-olefin polymerization catalyst of the present invention provides polypropylene with low CXS (23°C xylene soluble components) and high stereoregularity. be able to.
Specifically, by comparing Reference Examples 1 and 2 with Comparative Example 1, the solid component (A1), the silane compound (A2) having an alkenyl group, the alkoxysilane compound (A3), and the organoaluminum compound (A4) By contacting with at a high temperature, the content of di-n-butyl phthalate, which is an electron donor contained in the catalyst component (A), can be greatly reduced, and the CXS of the polymer obtained by polymerization ( 23 ° C. xylene soluble component) can be reduced, and by comparing Reference Example 1 and Comparative Example 1, the stereoregularity (mm fraction) of the polymer obtained by polymerization was able to be improved. I understand. In Comparative Example 2, the contact treatment was performed at a higher temperature than in Reference Examples 1 and 2. As a result, the content of di-n-butyl phthalate was further reduced, but the activity was greatly reduced. resulted in worsening.
Further, by comparing Examples 3 and 4 with Comparative Example 3, it was found that prepolymerization before the contact treatment at a high temperature further reduced -The content of n-butyl can be reduced, the CXS (23° C. xylene soluble component amount) of the polymer obtained by polymerization can be reduced, and the stereoregularity (mm fraction) is also improved.
Therefore, the examples are catalysts with extremely low CXS (23° C. xylene-soluble components) and capable of obtaining polymers with high stereoregularity, and excellent results are obtained as compared with the comparative examples. I can say.

INDUSTRIAL APPLICABILITY The α-olefin polymerization catalyst of the present invention has high performance in all catalytic performances such as stereoregularity, particle properties, and catalytic activity. It is industrially highly applicable.

Claims (5)

A method for producing a solid catalyst component (A) for α-olefin polymerization containing magnesium, titanium, halogen, an electron donor and an alkoxysilane compound, comprising:
Component (A1) below was prepolymerized using at least one olefin selected from the group consisting of ethylene, propylene, 1-butene, and 3-methyl-1-butene in the presence of an organoaluminum compound. After that, the component (A1) is contacted with the component (A2), the component (A3) and the component (A4) at a temperature of 50 to 110 ° C.,
A method for producing a solid catalyst component for α-olefin polymerization, wherein the content of the electron donor in the obtained solid catalyst component for α-olefin polymerization (A) is 40 μmol/g or less.
Component (A1): Solid component containing titanium, magnesium, halogen and an electron donor as essential components Component (A2): Silane compound having an alkenyl group Component (A3): Alkoxysilane compound [wherein the silane compound having an alkenyl group different from ]
Component (A4): Organoaluminum compound 2. The method for producing a solid catalyst component for α-olefin polymerization according to claim 1 , wherein said component (A2) is a vinylsilane compound. 3. The method for producing a solid catalyst component for α-olefin polymerization according to claim 1 or 2 , wherein said component (A3) is a silicon compound represented by the following general formula (1).
R ¹ R ² _m Si(OR ³ ) _n (1)
(wherein R ¹ represents a hydrocarbon group or a heteroatom-containing hydrocarbon group; R ² represents any free radical selected from hydrogen, halogen, hydrocarbon groups and heteroatom-containing hydrocarbon groups; R ³ represents It is a hydrocarbon group and represents 0≦m≦2, 1≦n≦3, and m+n=3.) An α-olefin polymerization catalyst characterized by comprising a solid catalyst component (A) for α-olefin polymerization obtained by the production method according to any one of claims 1 to 3 and the following component (B).
Component (B): Organoaluminum compound A method for producing an α-olefin polymer, which comprises homopolymerizing or copolymerizing an α-olefin using the α-olefin polymerization catalyst according to claim 4 .